1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c)  2019 Intel Corporation */
3
4#include "igc.h"
5
6#include <linux/module.h>
7#include <linux/device.h>
8#include <linux/pci.h>
9#include <linux/ptp_classify.h>
10#include <linux/clocksource.h>
11#include <linux/ktime.h>
12
13#define INCVALUE_MASK		0x7fffffff
14#define ISGN			0x80000000
15
16#define IGC_SYSTIM_OVERFLOW_PERIOD	(HZ * 60 * 9)
17#define IGC_PTP_TX_TIMEOUT		(HZ * 15)
18
19/* SYSTIM read access for I225 */
20void igc_ptp_read(struct igc_adapter *adapter, struct timespec64 *ts)
21{
22	struct igc_hw *hw = &adapter->hw;
23	u32 sec, nsec;
24
25	/* The timestamp is latched when SYSTIML is read. */
26	nsec = rd32(IGC_SYSTIML);
27	sec = rd32(IGC_SYSTIMH);
28
29	ts->tv_sec = sec;
30	ts->tv_nsec = nsec;
31}
32
33static void igc_ptp_write_i225(struct igc_adapter *adapter,
34			       const struct timespec64 *ts)
35{
36	struct igc_hw *hw = &adapter->hw;
37
38	wr32(IGC_SYSTIML, ts->tv_nsec);
39	wr32(IGC_SYSTIMH, ts->tv_sec);
40}
41
42static int igc_ptp_adjfine_i225(struct ptp_clock_info *ptp, long scaled_ppm)
43{
44	struct igc_adapter *igc = container_of(ptp, struct igc_adapter,
45					       ptp_caps);
46	struct igc_hw *hw = &igc->hw;
47	int neg_adj = 0;
48	u64 rate;
49	u32 inca;
50
51	if (scaled_ppm < 0) {
52		neg_adj = 1;
53		scaled_ppm = -scaled_ppm;
54	}
55	rate = scaled_ppm;
56	rate <<= 14;
57	rate = div_u64(rate, 78125);
58
59	inca = rate & INCVALUE_MASK;
60	if (neg_adj)
61		inca |= ISGN;
62
63	wr32(IGC_TIMINCA, inca);
64
65	return 0;
66}
67
68static int igc_ptp_adjtime_i225(struct ptp_clock_info *ptp, s64 delta)
69{
70	struct igc_adapter *igc = container_of(ptp, struct igc_adapter,
71					       ptp_caps);
72	struct timespec64 now, then = ns_to_timespec64(delta);
73	unsigned long flags;
74
75	spin_lock_irqsave(&igc->tmreg_lock, flags);
76
77	igc_ptp_read(igc, &now);
78	now = timespec64_add(now, then);
79	igc_ptp_write_i225(igc, (const struct timespec64 *)&now);
80
81	spin_unlock_irqrestore(&igc->tmreg_lock, flags);
82
83	return 0;
84}
85
86static int igc_ptp_gettimex64_i225(struct ptp_clock_info *ptp,
87				   struct timespec64 *ts,
88				   struct ptp_system_timestamp *sts)
89{
90	struct igc_adapter *igc = container_of(ptp, struct igc_adapter,
91					       ptp_caps);
92	struct igc_hw *hw = &igc->hw;
93	unsigned long flags;
94
95	spin_lock_irqsave(&igc->tmreg_lock, flags);
96
97	ptp_read_system_prets(sts);
98	ts->tv_nsec = rd32(IGC_SYSTIML);
99	ts->tv_sec = rd32(IGC_SYSTIMH);
100	ptp_read_system_postts(sts);
101
102	spin_unlock_irqrestore(&igc->tmreg_lock, flags);
103
104	return 0;
105}
106
107static int igc_ptp_settime_i225(struct ptp_clock_info *ptp,
108				const struct timespec64 *ts)
109{
110	struct igc_adapter *igc = container_of(ptp, struct igc_adapter,
111					       ptp_caps);
112	unsigned long flags;
113
114	spin_lock_irqsave(&igc->tmreg_lock, flags);
115
116	igc_ptp_write_i225(igc, ts);
117
118	spin_unlock_irqrestore(&igc->tmreg_lock, flags);
119
120	return 0;
121}
122
123static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
124				       struct ptp_clock_request *rq, int on)
125{
126	return -EOPNOTSUPP;
127}
128
129/**
130 * igc_ptp_systim_to_hwtstamp - convert system time value to HW timestamp
131 * @adapter: board private structure
132 * @hwtstamps: timestamp structure to update
133 * @systim: unsigned 64bit system time value
134 *
135 * We need to convert the system time value stored in the RX/TXSTMP registers
136 * into a hwtstamp which can be used by the upper level timestamping functions.
137 *
138 * Returns 0 on success.
139 **/
140static int igc_ptp_systim_to_hwtstamp(struct igc_adapter *adapter,
141				      struct skb_shared_hwtstamps *hwtstamps,
142				      u64 systim)
143{
144	switch (adapter->hw.mac.type) {
145	case igc_i225:
146		memset(hwtstamps, 0, sizeof(*hwtstamps));
147		/* Upper 32 bits contain s, lower 32 bits contain ns. */
148		hwtstamps->hwtstamp = ktime_set(systim >> 32,
149						systim & 0xFFFFFFFF);
150		break;
151	default:
152		return -EINVAL;
153	}
154	return 0;
155}
156
157/**
158 * igc_ptp_rx_pktstamp - Retrieve timestamp from Rx packet buffer
159 * @q_vector: Pointer to interrupt specific structure
160 * @va: Pointer to address containing Rx buffer
161 * @skb: Buffer containing timestamp and packet
162 *
163 * This function retrieves the timestamp saved in the beginning of packet
164 * buffer. While two timestamps are available, one in timer0 reference and the
165 * other in timer1 reference, this function considers only the timestamp in
166 * timer0 reference.
167 */
168void igc_ptp_rx_pktstamp(struct igc_q_vector *q_vector, __le32 *va,
169			 struct sk_buff *skb)
170{
171	struct igc_adapter *adapter = q_vector->adapter;
172	u64 regval;
173	int adjust;
174
175	/* Timestamps are saved in little endian at the beginning of the packet
176	 * buffer following the layout:
177	 *
178	 * DWORD: | 0              | 1              | 2              | 3              |
179	 * Field: | Timer1 SYSTIML | Timer1 SYSTIMH | Timer0 SYSTIML | Timer0 SYSTIMH |
180	 *
181	 * SYSTIML holds the nanoseconds part while SYSTIMH holds the seconds
182	 * part of the timestamp.
183	 */
184	regval = le32_to_cpu(va[2]);
185	regval |= (u64)le32_to_cpu(va[3]) << 32;
186	igc_ptp_systim_to_hwtstamp(adapter, skb_hwtstamps(skb), regval);
187
188	/* Adjust timestamp for the RX latency based on link speed */
189	switch (adapter->link_speed) {
190	case SPEED_10:
191		adjust = IGC_I225_RX_LATENCY_10;
192		break;
193	case SPEED_100:
194		adjust = IGC_I225_RX_LATENCY_100;
195		break;
196	case SPEED_1000:
197		adjust = IGC_I225_RX_LATENCY_1000;
198		break;
199	case SPEED_2500:
200		adjust = IGC_I225_RX_LATENCY_2500;
201		break;
202	default:
203		adjust = 0;
204		netdev_warn_once(adapter->netdev, "Imprecise timestamp\n");
205		break;
206	}
207	skb_hwtstamps(skb)->hwtstamp =
208		ktime_sub_ns(skb_hwtstamps(skb)->hwtstamp, adjust);
209}
210
211static void igc_ptp_disable_rx_timestamp(struct igc_adapter *adapter)
212{
213	struct igc_hw *hw = &adapter->hw;
214	u32 val;
215	int i;
216
217	wr32(IGC_TSYNCRXCTL, 0);
218
219	for (i = 0; i < adapter->num_rx_queues; i++) {
220		val = rd32(IGC_SRRCTL(i));
221		val &= ~IGC_SRRCTL_TIMESTAMP;
222		wr32(IGC_SRRCTL(i), val);
223	}
224
225	val = rd32(IGC_RXPBS);
226	val &= ~IGC_RXPBS_CFG_TS_EN;
227	wr32(IGC_RXPBS, val);
228}
229
230static void igc_ptp_enable_rx_timestamp(struct igc_adapter *adapter)
231{
232	struct igc_hw *hw = &adapter->hw;
233	u32 val;
234	int i;
235
236	val = rd32(IGC_RXPBS);
237	val |= IGC_RXPBS_CFG_TS_EN;
238	wr32(IGC_RXPBS, val);
239
240	for (i = 0; i < adapter->num_rx_queues; i++) {
241		val = rd32(IGC_SRRCTL(i));
242		/* FIXME: For now, only support retrieving RX timestamps from
243		 * timer 0.
244		 */
245		val |= IGC_SRRCTL_TIMER1SEL(0) | IGC_SRRCTL_TIMER0SEL(0) |
246		       IGC_SRRCTL_TIMESTAMP;
247		wr32(IGC_SRRCTL(i), val);
248	}
249
250	val = IGC_TSYNCRXCTL_ENABLED | IGC_TSYNCRXCTL_TYPE_ALL |
251	      IGC_TSYNCRXCTL_RXSYNSIG;
252	wr32(IGC_TSYNCRXCTL, val);
253}
254
255static void igc_ptp_disable_tx_timestamp(struct igc_adapter *adapter)
256{
257	struct igc_hw *hw = &adapter->hw;
258
259	wr32(IGC_TSYNCTXCTL, 0);
260}
261
262static void igc_ptp_enable_tx_timestamp(struct igc_adapter *adapter)
263{
264	struct igc_hw *hw = &adapter->hw;
265
266	wr32(IGC_TSYNCTXCTL, IGC_TSYNCTXCTL_ENABLED | IGC_TSYNCTXCTL_TXSYNSIG);
267
268	/* Read TXSTMP registers to discard any timestamp previously stored. */
269	rd32(IGC_TXSTMPL);
270	rd32(IGC_TXSTMPH);
271}
272
273/**
274 * igc_ptp_set_timestamp_mode - setup hardware for timestamping
275 * @adapter: networking device structure
276 * @config: hwtstamp configuration
277 *
278 * Return: 0 in case of success, negative errno code otherwise.
279 */
280static int igc_ptp_set_timestamp_mode(struct igc_adapter *adapter,
281				      struct hwtstamp_config *config)
282{
283	/* reserved for future extensions */
284	if (config->flags)
285		return -EINVAL;
286
287	switch (config->tx_type) {
288	case HWTSTAMP_TX_OFF:
289		igc_ptp_disable_tx_timestamp(adapter);
290		break;
291	case HWTSTAMP_TX_ON:
292		igc_ptp_enable_tx_timestamp(adapter);
293		break;
294	default:
295		return -ERANGE;
296	}
297
298	switch (config->rx_filter) {
299	case HWTSTAMP_FILTER_NONE:
300		igc_ptp_disable_rx_timestamp(adapter);
301		break;
302	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
303	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
304	case HWTSTAMP_FILTER_PTP_V2_EVENT:
305	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
306	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
307	case HWTSTAMP_FILTER_PTP_V2_SYNC:
308	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
309	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
310	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
311	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
312	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
313	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
314	case HWTSTAMP_FILTER_NTP_ALL:
315	case HWTSTAMP_FILTER_ALL:
316		igc_ptp_enable_rx_timestamp(adapter);
317		config->rx_filter = HWTSTAMP_FILTER_ALL;
318		break;
319	default:
320		return -ERANGE;
321	}
322
323	return 0;
324}
325
326/* Requires adapter->ptp_tx_lock held by caller. */
327static void igc_ptp_tx_timeout(struct igc_adapter *adapter)
328{
329	struct igc_hw *hw = &adapter->hw;
330
331	dev_kfree_skb_any(adapter->ptp_tx_skb);
332	adapter->ptp_tx_skb = NULL;
333	adapter->tx_hwtstamp_timeouts++;
334	/* Clear the tx valid bit in TSYNCTXCTL register to enable interrupt. */
335	rd32(IGC_TXSTMPH);
336	netdev_warn(adapter->netdev, "Tx timestamp timeout\n");
337}
338
339void igc_ptp_tx_hang(struct igc_adapter *adapter)
340{
341	unsigned long flags;
342
343	spin_lock_irqsave(&adapter->ptp_tx_lock, flags);
344
345	if (!adapter->ptp_tx_skb)
346		goto unlock;
347
348	if (time_is_after_jiffies(adapter->ptp_tx_start + IGC_PTP_TX_TIMEOUT))
349		goto unlock;
350
351	igc_ptp_tx_timeout(adapter);
352
353unlock:
354	spin_unlock_irqrestore(&adapter->ptp_tx_lock, flags);
355}
356
357/**
358 * igc_ptp_tx_hwtstamp - utility function which checks for TX time stamp
359 * @adapter: Board private structure
360 *
361 * If we were asked to do hardware stamping and such a time stamp is
362 * available, then it must have been for this skb here because we only
363 * allow only one such packet into the queue.
364 *
365 * Context: Expects adapter->ptp_tx_lock to be held by caller.
366 */
367static void igc_ptp_tx_hwtstamp(struct igc_adapter *adapter)
368{
369	struct sk_buff *skb = adapter->ptp_tx_skb;
370	struct skb_shared_hwtstamps shhwtstamps;
371	struct igc_hw *hw = &adapter->hw;
372	int adjust = 0;
373	u64 regval;
374
375	if (WARN_ON_ONCE(!skb))
376		return;
377
378	regval = rd32(IGC_TXSTMPL);
379	regval |= (u64)rd32(IGC_TXSTMPH) << 32;
380	if (igc_ptp_systim_to_hwtstamp(adapter, &shhwtstamps, regval))
381		return;
382
383	switch (adapter->link_speed) {
384	case SPEED_10:
385		adjust = IGC_I225_TX_LATENCY_10;
386		break;
387	case SPEED_100:
388		adjust = IGC_I225_TX_LATENCY_100;
389		break;
390	case SPEED_1000:
391		adjust = IGC_I225_TX_LATENCY_1000;
392		break;
393	case SPEED_2500:
394		adjust = IGC_I225_TX_LATENCY_2500;
395		break;
396	}
397
398	shhwtstamps.hwtstamp =
399		ktime_add_ns(shhwtstamps.hwtstamp, adjust);
400
401	adapter->ptp_tx_skb = NULL;
402
403	/* Notify the stack and free the skb after we've unlocked */
404	skb_tstamp_tx(skb, &shhwtstamps);
405	dev_kfree_skb_any(skb);
406}
407
408/**
409 * igc_ptp_tx_work
410 * @work: pointer to work struct
411 *
412 * This work function checks the TSYNCTXCTL valid bit to determine when
413 * a timestamp has been taken for the current stored skb.
414 */
415static void igc_ptp_tx_work(struct work_struct *work)
416{
417	struct igc_adapter *adapter = container_of(work, struct igc_adapter,
418						   ptp_tx_work);
419	struct igc_hw *hw = &adapter->hw;
420	unsigned long flags;
421	u32 tsynctxctl;
422
423	spin_lock_irqsave(&adapter->ptp_tx_lock, flags);
424
425	if (!adapter->ptp_tx_skb)
426		goto unlock;
427
428	tsynctxctl = rd32(IGC_TSYNCTXCTL);
429	tsynctxctl &= IGC_TSYNCTXCTL_TXTT_0;
430	if (!tsynctxctl) {
431		WARN_ONCE(1, "Received a TSTAMP interrupt but no TSTAMP is ready.\n");
432		goto unlock;
433	}
434
435	igc_ptp_tx_hwtstamp(adapter);
436
437unlock:
438	spin_unlock_irqrestore(&adapter->ptp_tx_lock, flags);
439}
440
441/**
442 * igc_ptp_set_ts_config - set hardware time stamping config
443 * @netdev: network interface device structure
444 * @ifr: interface request data
445 *
446 **/
447int igc_ptp_set_ts_config(struct net_device *netdev, struct ifreq *ifr)
448{
449	struct igc_adapter *adapter = netdev_priv(netdev);
450	struct hwtstamp_config config;
451	int err;
452
453	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
454		return -EFAULT;
455
456	err = igc_ptp_set_timestamp_mode(adapter, &config);
457	if (err)
458		return err;
459
460	/* save these settings for future reference */
461	memcpy(&adapter->tstamp_config, &config,
462	       sizeof(adapter->tstamp_config));
463
464	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
465		-EFAULT : 0;
466}
467
468/**
469 * igc_ptp_get_ts_config - get hardware time stamping config
470 * @netdev: network interface device structure
471 * @ifr: interface request data
472 *
473 * Get the hwtstamp_config settings to return to the user. Rather than attempt
474 * to deconstruct the settings from the registers, just return a shadow copy
475 * of the last known settings.
476 **/
477int igc_ptp_get_ts_config(struct net_device *netdev, struct ifreq *ifr)
478{
479	struct igc_adapter *adapter = netdev_priv(netdev);
480	struct hwtstamp_config *config = &adapter->tstamp_config;
481
482	return copy_to_user(ifr->ifr_data, config, sizeof(*config)) ?
483		-EFAULT : 0;
484}
485
486/**
487 * igc_ptp_init - Initialize PTP functionality
488 * @adapter: Board private structure
489 *
490 * This function is called at device probe to initialize the PTP
491 * functionality.
492 */
493void igc_ptp_init(struct igc_adapter *adapter)
494{
495	struct net_device *netdev = adapter->netdev;
496	struct igc_hw *hw = &adapter->hw;
497
498	switch (hw->mac.type) {
499	case igc_i225:
500		snprintf(adapter->ptp_caps.name, 16, "%pm", netdev->dev_addr);
501		adapter->ptp_caps.owner = THIS_MODULE;
502		adapter->ptp_caps.max_adj = 62499999;
503		adapter->ptp_caps.adjfine = igc_ptp_adjfine_i225;
504		adapter->ptp_caps.adjtime = igc_ptp_adjtime_i225;
505		adapter->ptp_caps.gettimex64 = igc_ptp_gettimex64_i225;
506		adapter->ptp_caps.settime64 = igc_ptp_settime_i225;
507		adapter->ptp_caps.enable = igc_ptp_feature_enable_i225;
508		break;
509	default:
510		adapter->ptp_clock = NULL;
511		return;
512	}
513
514	spin_lock_init(&adapter->ptp_tx_lock);
515	spin_lock_init(&adapter->tmreg_lock);
516	INIT_WORK(&adapter->ptp_tx_work, igc_ptp_tx_work);
517
518	adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
519	adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
520
521	adapter->prev_ptp_time = ktime_to_timespec64(ktime_get_real());
522	adapter->ptp_reset_start = ktime_get();
523
524	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_caps,
525						&adapter->pdev->dev);
526	if (IS_ERR(adapter->ptp_clock)) {
527		adapter->ptp_clock = NULL;
528		netdev_err(netdev, "ptp_clock_register failed\n");
529	} else if (adapter->ptp_clock) {
530		netdev_info(netdev, "PHC added\n");
531		adapter->ptp_flags |= IGC_PTP_ENABLED;
532	}
533}
534
535static void igc_ptp_time_save(struct igc_adapter *adapter)
536{
537	igc_ptp_read(adapter, &adapter->prev_ptp_time);
538	adapter->ptp_reset_start = ktime_get();
539}
540
541static void igc_ptp_time_restore(struct igc_adapter *adapter)
542{
543	struct timespec64 ts = adapter->prev_ptp_time;
544	ktime_t delta;
545
546	delta = ktime_sub(ktime_get(), adapter->ptp_reset_start);
547
548	timespec64_add_ns(&ts, ktime_to_ns(delta));
549
550	igc_ptp_write_i225(adapter, &ts);
551}
552
553/**
554 * igc_ptp_suspend - Disable PTP work items and prepare for suspend
555 * @adapter: Board private structure
556 *
557 * This function stops the overflow check work and PTP Tx timestamp work, and
558 * will prepare the device for OS suspend.
559 */
560void igc_ptp_suspend(struct igc_adapter *adapter)
561{
562	if (!(adapter->ptp_flags & IGC_PTP_ENABLED))
563		return;
564
565	cancel_work_sync(&adapter->ptp_tx_work);
566	dev_kfree_skb_any(adapter->ptp_tx_skb);
567	adapter->ptp_tx_skb = NULL;
568
569	if (pci_device_is_present(adapter->pdev))
570		igc_ptp_time_save(adapter);
571}
572
573/**
574 * igc_ptp_stop - Disable PTP device and stop the overflow check.
575 * @adapter: Board private structure.
576 *
577 * This function stops the PTP support and cancels the delayed work.
578 **/
579void igc_ptp_stop(struct igc_adapter *adapter)
580{
581	igc_ptp_suspend(adapter);
582
583	if (adapter->ptp_clock) {
584		ptp_clock_unregister(adapter->ptp_clock);
585		netdev_info(adapter->netdev, "PHC removed\n");
586		adapter->ptp_flags &= ~IGC_PTP_ENABLED;
587	}
588}
589
590/**
591 * igc_ptp_reset - Re-enable the adapter for PTP following a reset.
592 * @adapter: Board private structure.
593 *
594 * This function handles the reset work required to re-enable the PTP device.
595 **/
596void igc_ptp_reset(struct igc_adapter *adapter)
597{
598	struct igc_hw *hw = &adapter->hw;
599	unsigned long flags;
600
601	/* reset the tstamp_config */
602	igc_ptp_set_timestamp_mode(adapter, &adapter->tstamp_config);
603
604	spin_lock_irqsave(&adapter->tmreg_lock, flags);
605
606	switch (adapter->hw.mac.type) {
607	case igc_i225:
608		wr32(IGC_TSAUXC, 0x0);
609		wr32(IGC_TSSDP, 0x0);
610		wr32(IGC_TSIM, IGC_TSICR_INTERRUPTS);
611		wr32(IGC_IMS, IGC_IMS_TS);
612		break;
613	default:
614		/* No work to do. */
615		goto out;
616	}
617
618	/* Re-initialize the timer. */
619	if (hw->mac.type == igc_i225) {
620		igc_ptp_time_restore(adapter);
621	} else {
622		timecounter_init(&adapter->tc, &adapter->cc,
623				 ktime_to_ns(ktime_get_real()));
624	}
625out:
626	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
627
628	wrfl();
629}
630